Author Topic: [LEL17] Mechanic's advices for the next LEL  (Read 23762 times)

[LEL17] Mechanic's advices for the next LEL
« on: 10 August, 2017, 07:23:19 am »
Hi all,

Now that the dust has (a bit) settled, I would like to share a few thoughts about my LEL experience as a mechanic at Barnard Castle. I think this could be cast into recommendations for new riders on LEL 2021. Please feel free to comment or complete.

Of course, I'm perfectly aware that the majority of the riders don't need any of these recommendations, but from my place at the mechanics stand, I probably saw some of the most poorly prepared riders. I saw many problems that could have been avoided with better mechanical preparation. I don't mean at all that all the riders who showed up at the mechanics stand were poorly prepared. Some were just unlucky, but others had clearly inadequate bicycles, and with the continuous growth in the number of riders, we should probably expect to see a larger number of unprepared riders in the future.
 
So here we go:


1) Brake/shifter levers: All modern brake/shifter levers tend to chew out and destroy the gear cables, especially when exposed to rain and fine grit as you will encounter on the LEL route. This is true no matter you use Shimano, Campagnolo or Sram levers. We had to change cables on all three flavours of levers. Most of them were badly chewed right into the brake lever. The best solution is to use downtube or bar end shifters, but if you really prefer brake/shifter levers, make sure you have new cables fitted and properly lubricated just before LEL.

2) Cable routing: Changing a gear cable on a modern carbon fiber frame with internal cable routing takes many times longer than on a more traditional bicycle with external routing. Actually, internally routed cables are easier to change with the bottom bracket off the frame, but don't expect the basic mechanics stand at the controls to be able to take off your bottom bracket. Many of these bottom brackets are press fit and requires special tooling that you will find in a proper bicycle shop, but not in a control. It is still possible to change a cable without removing the bottom bracket, but it is a very long and tedious job. One of them took more than an hour of work for three volunteers. While the volunteers are working for a long time for one rider, they cannot care for all the others who are waiting behind. The message is: either use a bicycle with external gear cables, or, if you really insist on having internal cables: change them before the ride, and practice changing them yourself!

3) Tubeless tyres: These look really interesting due to their ability to self repair punctures with inner sealant, and their ability to run safely at a lower pressure. However, at the Barnard Castle control, we had to care for two riders with tubeless tyres that were beyond any hope of self repair. A tube was fitted in these tyres, but the job was quite tedious due to the tyres being very tightly fitted on the rim. Another rider came in with a wheel that presumably needed truing, as the bicycle was vibrating dangerously at high speed. Actually, his wheel was reasonably true, the problem was that all the sealant sealed itself for no obvious reason on one end of the tyre, acting as a big weight imbalance. I do not mean that you should not use tubeless tyres, but please take into account what might happens to you.

4) Bicycle parts for sale: Some controls, but not all, will have a basic set of bicycle parts for sale, like tubes, chains, cables, etc.  These parts should be seen as an emergency help only, we are not a regular bicycle shop. All riders are expected to carry with them everything they need to complete the ride. So if you ask us for one spare tube, we will happily sell you one, provided that we have one that fits your bicycle. If you ask for 4 or 5 tubes, as some riders did, we will politely tell you to go to the nearest bike shop. If your bicycle needs unusual parts (for example: specific brake pads for carbon rims), bring your own, don't expect to find spares for sale at controls.

5) Electronic shifting: Many riders were let down by the battery of their electronic shifters. These batteries are simply not designed to last for 1400 km in the cold and rainy LEL weather. If you bring your own charger, you may be able to charge your battery, provided a mains socket is available. If you have no charger, the volunteers will not be able to help you.

6) GPS devices: Do not expect the volunteers to be able to solve any problem with your device. If you need charging and have your own charger, you may be able to use a mains socket. If you have no charger, you will not be able to charge your device.

7) Chain oiling and tyres pumping: Riders are expected to show a minimum of self-sufficiency. If your chain needs oiling, or your tyres need pumping, we will happily lend you a bottle of lube or a proper track pump. Asking volunteers to do it for you is probably asking for too much. Volunteers are very busy at solving other problems. If you feel that you are too tired for using a pump by yourself, consider going to bed for an hour or two.

8) Low spoke count wheels: These wheels are clearly not suitable for a long distance event like LEL. If you  have only 16 spokes and break just one of them, chances are that your bicycle will be unrideable. With a more traditional wheel with 28, 32 or 36 spokes, you can break a spoke a keep riding to the next control. Moreover, low spoke count wheels often have special proprietary spokes, and unless you carry your own spare spokes, no one will be able to fix your wheel at the next control.


Alain

Re: Mechanic's advices for the next LEL
« Reply #1 on: 10 August, 2017, 07:50:56 am »
Thank you for the pointers.  I would add if you are using special spokes aero direct pull then please consider carrying a couple of each length that you require taped to your bike.

I had 1 rider get a little irate that I could not true a low spoke count wheel when he had broken such a spoke.  I would suggest that 16 spokes is too few to have in a wheel for this event.  This particular wheel had fewer.

Geoff
1 of the mechanics at Spalding
Only those that dare to go too far, know how far they can go.   T S Elliot

Re: Mechanic's advices for the next LEL
« Reply #2 on: 10 August, 2017, 08:29:16 am »
I have no experience of gear or brake cables as i run hydraulic discs for many of the reasons stated.

I do think that you are being unfair to Di2.  This was not arctic weather.  The temperature was in the standard operating temperature for Di2 at all times.  Whilst Yad Moss was cold we did not have ice!

Di2  batteries are rated for 1700km  of normal use at these temperatures.  Batteries of course degrade with time and some of the first generation batteries are possibly at 50% capacity.  However if you do not bring a charger with you and some form of charging then you are an idiot.  The charger weighs a negligible amount and can be used with a 4 AA USB charger pack which could be left in a bag drop if required.  Di2 is almost certainly the very best mechanism for long distance riding as it completely obviates the need for cables, adjustments, etc.  However just like Garmins, mobile phones and other advances it has a learning curve.

whosatthewheel

Re: Mechanic's advices for the next LEL
« Reply #3 on: 10 August, 2017, 08:30:58 am »

1) Brake/shifter levers: All modern brake/shifter levers tend to chew out and destroy the gear cables, especially when exposed to rain and fine grit as you will encounter on the LEL route. This is true no matter you use Shimano, Campagnolo or Sram levers. We had to change cables on all three flavours of levers. Most of them were badly chewed right into the brake lever. The best solution is to use downtube or bar end shifters, but if you really prefer brake/shifter levers, make sure you have new cables fitted and properly lubricated just before LEL.


Alain

Are you really suggesting to go back to downtube shifters and bar end shifters?

There was a generation of Shimano STIs that indeed chewed gear cables, most notably the 5600 and to a lesser extent the 5700. The more recent ones seem immune from that problem. I have never owned SRAM and can't vouch for these (although they did seem to have other issues). Campagnolo shifters have never chewed gear cables as far as I am aware.

I have owned various Ergo, mach 2 and mach 3 versions and never had to replace a cable that I remember.

I would say if a cable can't cope with a thousand miles of riding, there was a problem in its installation in the first place..

Advising to go back to downtube shifters seem a bit excessive... I can't even think of any modern framset that has bosses for downtube shifters... it would be a case of ramaging the local recycling centre in search for something suitable.. probably one step too far

Zed43

  • prefers UK hills over Dutch mountains
Re: Mechanic's advices for the next LEL
« Reply #4 on: 10 August, 2017, 08:39:31 am »
Regarding electronic shifting, I think the Di2 battery may last 1400km unless you have a wireless transmitter to record your gearshifts on your GPS.

Still, bringing the charger and a USB power pack and packing these on your bike (instead of in a dropbag) is good insurance. Don't forget to pack electronics in a waterproof bag (1 litre Ziploc is ideal).

I had a 20Ah power pack on the bike and another one in my Brampton dropbag. The one on the bike was enough to keep the Garmin, lights, Di2 and phone running  (I do keep my phone in flight mode most of the time though). Bringing a power pack makes you independent of the availability of wall sockets.

Sent from my SM-A520F using Tapatalk


Re: Mechanic's advices for the next LEL
« Reply #5 on: 10 August, 2017, 08:42:56 am »
Few people know that the gear changer nipples on STIs and Ergos are different sizes. Put the wrong one in, and you'll struggle to get them out.

 Andreas Keil rode Di2 in 2013, he didn't this year.

Re: Mechanic's advices for the next LEL
« Reply #6 on: 10 August, 2017, 08:48:17 am »
I experienced a chewed cable on a 5800 shifter (thankfully before LEL), and I know others that have too. The cable can't have been more than a few months old.

Regarding internal cable routing, the key here is a piece of plastic sheath that you thread over the old cable, pull through the frame, then do the reverse with the new cable. I'm not sure where you can buy this, mine came with the frame.

LittleWheelsandBig

  • Whimsy Rider
Re: Mechanic's advices for the next LEL
« Reply #7 on: 10 August, 2017, 08:52:05 am »
Campag Ergo also has a tendency to fatigue gear cables within the lever, though I've not had experience with 11sp Ergo (and don't want to).

I suggest replacing STI/Ergo cables annually on high mileage bikes to avoid broken cables.
Wheel meet again, don't know where, don't know when...

mattc

  • n.b. have grown beard since photo taken
    • Didcot Audaxes
Re: Mechanic's advices for the next LEL
« Reply #8 on: 10 August, 2017, 08:53:01 am »
Excellent post Alain!  :thumbsup:


Of course riders are free to choose their equipment, but info like this puts them in the best position to make an informed choice.
Has never ridden RAAM
---------
No.11  Because of the great host of those who dislike the least appearance of "swank " when they travel the roads and lanes. - From Kuklos' 39 Articles

Tomsk

  • Fueled by cake since 1957
    • tomsk.co.uk
Re: Mechanic's advices for the next LEL
« Reply #9 on: 10 August, 2017, 09:26:22 am »
Are you really suggesting to go back to downtube shifters and bar end shifters?

I really like the 7sp 105 down-tube levers on my [rather old] geared Audax bike, though bar-end shifters would perhaps be my choice on a new machine [as on my tourer]. But then I have slightly arthritic hands and appreciate the chance to keep them moving frequently. And, you can tell by feel what gear you're in - very useful at night.

Having failed to replace a gear cable on another's bike, on another ride and spent a fair bit of time fiddling around in the shed with my STI levers, I really like the ease of changing dt gear cables, plus having the friction only option: with a change of chain I could run any rear wheel bought/borrowed/cannibalised en-route.

whosatthewheel

Re: Mechanic's advices for the next LEL
« Reply #10 on: 10 August, 2017, 09:38:13 am »
My point is that we are in 2017... I know you can still buy Dura Ace downtube shifters, although I think they are indexed for 9 or 10 speed, can't remember. The choice of frames with bosses is pretty much down to zero... maybe Surly make something that weighs 3 kg and takes DT shifters? Not many people still have a bike with DT shifters (I do have one with 52 x 42 and a 23 freewheel at the back...) and those that do, might have an overall less reliable bike. I would definitively "risk" using STIs... maybe even go as far as investing 2 pounds in a new cable ahead of the event, safe in the knowledge that IT WILL last a thousand miles...

I thought discussions like this one had been buried by 1992  ;D

mattc

  • n.b. have grown beard since photo taken
    • Didcot Audaxes
Re: Mechanic's advices for the next LEL
« Reply #11 on: 10 August, 2017, 09:42:55 am »
I would definitively "risk" using STIs... maybe even go as far as investing 2 pounds in a new cable ahead of the event, safe in the knowledge that IT WILL last a thousand miles...

I thought discussions like this one had been buried by 1992  ;D

This is exactly what was advised at the start of the thread. Here ya go:

if you really prefer brake/shifter levers, make sure you have new cables fitted and properly lubricated just before LEL.


I'm not really sure why you're turning this into an argument  :-\
Has never ridden RAAM
---------
No.11  Because of the great host of those who dislike the least appearance of "swank " when they travel the roads and lanes. - From Kuklos' 39 Articles

Re: Mechanic's advices for the next LEL
« Reply #12 on: 10 August, 2017, 09:50:03 am »
3) Tubeless tyres: These look really interesting due to their ability to self repair punctures with inner sealant, and their ability to run safely at a lower pressure. However, at the Barnard Castle control, we had to care for two riders with tubeless tyres that were beyond any hope of self repair. A tube was fitted in these tyres, but the job was quite tedious due to the tyres being very tightly fitted on the rim. Another rider came in with a wheel that presumably needed truing, as the bicycle was vibrating dangerously at high speed. Actually, his wheel was reasonably true, the problem was that all the sealant sealed itself for no obvious reason on one end of the tyre, acting as a big weight imbalance. I do not mean that you should not use tubeless tyres, but please take into account what might happens to you.

Interesting...
My tubeless tyre / rim combination is not so hard to fit (needs a lever rather than just thumbs but no huge problem) but OTH it is very unlikely to be able to get the bead seated without an Airshot (or the Schwalbe copy "Tire Booster" or one of the new pumps with a reservoir).   I'd have liked to see more of those at controls, but in the absence it was not a huge problem for me to fit and complete the event with tubes that I put in myself.

hulver

  • I am a mole and I live in a hole.
Re: Mechanic's advices for the next LEL
« Reply #13 on: 10 August, 2017, 10:00:39 am »
Hi all,

Now that the dust has (a bit) settled, I would like to share a few thoughts about my LEL experience as a mechanic at Barnard Castle. I think this could be cast into recommendations for new riders on LEL 2021. Please feel free to comment or complete.

*snip a lot of good advice*

As one of the mechanics at Pocklington, I'd second most of this (although I'm not sure about getting rid of STIs) I'd certainly say get your gear and brake cables changed before any long ride. It's difficult to tell when they're wearing out, and if they snap it's a nightmare to get the old bits out of the shifter (ask yorkie). Change them, and then give them a few weeks to stretch so they can be adjusted before you go on the ride.

Make sure your adjusters work.

Take some spare spokes of the right size for your wheels. All your wheels, drive side and non-drive side. That should only require 3 spokes at most, although two of each spare would be good.

Don't use old tyres on the ride. Put fresh rubber on, and ride it for a while before the ride. Take a spare tyre with you, and another in one of your drop bags in case you use your spare.

Most of the work I did was changing tubes & tyres and adjusting gears. Several wheels with snapped spokes we could do nothing for because we didn't have the right sized spoke.

Re: Mechanic's advices for the next LEL
« Reply #14 on: 10 August, 2017, 10:04:24 am »
I had 1 rider get a little irate that I could not true a low spoke count wheel when he had broken such a spoke.  I would suggest that 16 spokes is too few to have in a wheel for this event.  This particular wheel had fewer.

Thank you Geoff! I just added a comment about this sort of wheels.

Re: Mechanic's advices for the next LEL
« Reply #15 on: 10 August, 2017, 10:12:20 am »
I do think that you are being unfair to Di2.  This was not arctic weather.  The temperature was in the standard operating temperature for Di2 at all times.  Whilst Yad Moss was cold we did not have ice!

Di2  batteries are rated for 1700km  of normal use at these temperatures.  Batteries of course degrade with time and some of the first generation batteries are possibly at 50% capacity.  However if you do not bring a charger with you and some form of charging then you are an idiot.  The charger weighs a negligible amount and can be used with a 4 AA USB charger pack which could be left in a bag drop if required.  Di2 is almost certainly the very best mechanism for long distance riding as it completely obviates the need for cables, adjustments, etc.  However just like Garmins, mobile phones and other advances it has a learning curve.

I'm sorry if you feel that I'm unfair. I have never used Di2 myself. I just met two riders at BC who had low Di2 batteries and no charger. I don't know how many riders suffered from the same problem at other controls.  Even if you bring your own charger, the ever growing need to charge phones, GPS and Di2 tend to exceed the number of available mains sockets at controls.

billyam998

  • LEL rider C6 2013 / B11 2017 / B4 2022
Re: Mechanic's advices for the next LEL
« Reply #16 on: 10 August, 2017, 10:19:01 am »
Regarding electronic shifting, I think the Di2 battery may last 1400km unless you have a wireless transmitter to record your gearshifts on your GPS.

Still, bringing the charger and a USB power pack and packing these on your bike (instead of in a dropbag) is good insurance. Don't forget to pack electronics in a waterproof bag (1 litre Ziploc is ideal).

I had a 20Ah power pack on the bike and another one in my Brampton dropbag. The one on the bike was enough to keep the Garmin, lights, Di2 and phone running  (I do keep my phone in flight mode most of the time though). Bringing a power pack makes you independent of the availability of wall sockets.

Sent from my SM-A520F using Tapatalk

My seat tube DI2 battery (with bluetooth transmitter) lasted the whole event easily - despite my clumsy shifting, still showing 40% charge. I had power packs in my drop bags (I only fully drained one of them) - keeping garmin going and, one on the bike, apart from a quick boost for my phone at great easton, I didn't need to seek out a socket for the rest of the ride.  There was a lot of discussion regarding power sources etc before the ride, for people to turn up and, expect charging facility to be freely available is in my mind rather inept, as are a lot of the other ridiculous requests - glad I wasn't around when someone demanded their tyres be pumped up

arallsopp

  • Beansontoast
    • Barring Mechanicals Blog
Re: Mechanic's advices for the next LEL
« Reply #17 on: 10 August, 2017, 10:22:14 am »
Thanks for posting this. Puts us all in a good position to judge the compromises / advantages / relative safety of various choices we may be able to make. Even if its just back of the mind, "Next time I change X..."

The 'bents are always a bit of a law unto themselves. Nothing necessarily fits quite the way you'd hope, but I am finding a slow fluency towards better choices.


  • Bar end shifters seem to have proven reliability, and teamed with a 2x10 spd drive train there are enough tolerances to absorb many of LEL's assaults.
  • I'm still 50/50 with cable actuated disks vs. hydros. My experience is that the former are more likely to go wrong, but are easier to fix when they do. A problem with a hydro mid ride can be catastrophic, so newly fitted cables is probably the safest way
  • I'm liking schwalbe durano plus at the moment. I can't de-weight the bike and my view of bumps can be compromised, so I need something that'll take a few hits without grumbling. Fit new tyres a week before the event. If budget squeezes, you can always re-fit the old ones afterwards. Spare tyres will get used eventually, and there's never a better time to have lightly seasoned rubber.

Again, the main rule is ride it all first, a lot, then get it all checked, replace and service whatever needs loving, then ride it a bit more before the day.

Love words, hate lulu? Buy "Barring Mechanicals" on Amazon UK or US

billyam998

  • LEL rider C6 2013 / B11 2017 / B4 2022
Re: Mechanic's advices for the next LEL
« Reply #18 on: 10 August, 2017, 10:26:12 am »
I do think that you are being unfair to Di2.  This was not arctic weather.  The temperature was in the standard operating temperature for Di2 at all times.  Whilst Yad Moss was cold we did not have ice!

Di2  batteries are rated for 1700km  of normal use at these temperatures.  Batteries of course degrade with time and some of the first generation batteries are possibly at 50% capacity.  However if you do not bring a charger with you and some form of charging then you are an idiot.  The charger weighs a negligible amount and can be used with a 4 AA USB charger pack which could be left in a bag drop if required.  Di2 is almost certainly the very best mechanism for long distance riding as it completely obviates the need for cables, adjustments, etc.  However just like Garmins, mobile phones and other advances it has a learning curve.

I'm sorry if you feel that I'm unfair. I have never used Di2 myself. I just met two riders at BC who had low Di2 batteries and no charger. I don't know how many riders suffered from the same problem at other controls.  Even if you bring your own charger, the ever growing need to charge phones, GPS and Di2 tend to exceed the number of available mains sockets at controls.
I think your view is based on limited exposure to Di2, I prior to my most recent bike was hardcore campag and, swore never to change, however, the fact that changing at the end of long rides was becoming an increasingly difficult task meant I had to alter my thinking. The Di2 has many advantages once you have got your head around it all. Battery life really should not be an issue and, even if it is, the charger and, a decent power pack are light/compact enough to carry with you - I did, but didn't need them. Before you pour scorn on it you should at least seek out a more balanced view gained from exposure to it in differing circumstances.

jiberjaber

  • ... Fancy Pants \o/ ...
  • ACME S&M^2
Re: Mechanic's advices for the next LEL
« Reply #19 on: 10 August, 2017, 10:30:12 am »
I do think that you are being unfair to Di2.  This was not arctic weather.  The temperature was in the standard operating temperature for Di2 at all times.  Whilst Yad Moss was cold we did not have ice!

Di2  batteries are rated for 1700km  of normal use at these temperatures.  Batteries of course degrade with time and some of the first generation batteries are possibly at 50% capacity.  However if you do not bring a charger with you and some form of charging then you are an idiot.  The charger weighs a negligible amount and can be used with a 4 AA USB charger pack which could be left in a bag drop if required.  Di2 is almost certainly the very best mechanism for long distance riding as it completely obviates the need for cables, adjustments, etc.  However just like Garmins, mobile phones and other advances it has a learning curve.

I'm sorry if you feel that I'm unfair. I have never used Di2 myself. I just met two riders at BC who had low Di2 batteries and no charger. I don't know how many riders suffered from the same problem at other controls.  Even if you bring your own charger, the ever growing need to charge phones, GPS and Di2 tend to exceed the number of available mains sockets at controls.

It would be good to have a quantitative view on DI2 usage.  Mine was fine through the event, as a precaution, I gave it 30 mins charge on the way back at Spalding which took it from 40 to 100%   I think broad statements like the initial post, whilst well meaning perhaps, make it sound like it's a none starter for long distance riding... when in reality it is not the case.  You could easily make the case if the number of broken mechanical gear cables were taken relative to riders that everyone should have been on fixed (there was also a few freewheel failures as well :) ).

Bikes are not a case of fit and forget when it comes to maintenance, which I think is the key message here :)
Regards,

Joergen

Re: Mechanic's advices for the next LEL
« Reply #20 on: 10 August, 2017, 10:37:43 am »
Are you really suggesting to go back to downtube shifters and bar end shifters?
...
 I can't even think of any modern framset that has bosses for downtube shifters

If reliability is your no 1 decision criteria, my answer is yes. I think Ergo / STI levers are an excellent thing for criterium racers who need to shift very often and very quickly without moving their hands from the bar. But for audax, do we really need that?

I agree with your point regarding the availability of frames for downtube shifters, but I have bar end shifters on my audax bike and on our tandem, and never felt the need for anything better. Actually, I fitted the bar end shifters on the tandem after I got fed up of changing chewed out cables from our previous 9sp Ergo levers.

CrinklyLion

  • The one with devious, cake-pushing ways....
Re: Mechanic's advices for the next LEL
« Reply #21 on: 10 August, 2017, 10:46:46 am »
Bikes are not a case of fit and forget when it comes to maintenance, which I think is the key message here :)

And maybe that if you are going to use relatively unusual/tricky to repair kit, you need to make sure that you have the appropriate spares, tools, knowledge and skills to resolve problems that may arise with it, rather than expecting an unpaid volunteer who has had about 4 hours sleep in the past 3 days to sort it out.  CrinklyUncle's new bike uses di2.  He started with fully charged batteries, carried a charger and knew how to tweak the gears himself so did so when it was necessary.  The only reason I clocked that he has Di2 was a comment in passing somewhere, after the event, about him lending the charger to someone else...

I found it interesting that a couple of times I heard volunteers who were supporting Alain (who did man the workstands in BC almost permanently) comment that they were a bit nervous to work on a bike because it was a particularly expensive one. They took the responsibility extremely seriously, and were committed, if they possibly could, to getting people back out on the road and round the ride whatever machine they were on.

Btw - despite his _excellent_ English, Alain is in fact French (clue's in the name) so is posting in a foreign language.  Perhaps people could look look for the helpful intention in his post rather than interpreting it as 'pouring scorn' on a particular technology?  Actually, I should go and find the similar post from 4 years ago by a volunteer who spent the entire event spannering to see how it compares...

mattc

  • n.b. have grown beard since photo taken
    • Didcot Audaxes
Re: Mechanic's advices for the next LEL
« Reply #22 on: 10 August, 2017, 10:47:34 am »
My granddad smoked like a chimney and lived to 107.

Just sayin ...

[ EDIT: this is not in response to Crinkly's post!!! ]
Has never ridden RAAM
---------
No.11  Because of the great host of those who dislike the least appearance of "swank " when they travel the roads and lanes. - From Kuklos' 39 Articles

CrinklyLion

  • The one with devious, cake-pushing ways....
Re: Mechanic's advices for the next LEL
« Reply #23 on: 10 August, 2017, 10:54:48 am »
I'm intrigued - what are you just sayin'?

Re: Mechanic's advices for the next LEL
« Reply #24 on: 10 August, 2017, 11:08:45 am »
Alain describes sealant solidifying in one part of a tubeless tyre.

In my experience it's probably caused by someone trying to seal and seat a tubeless tyre with a CO2 canister. The sudden rush of cold air freezes the sealant which then stays solid and is completely useless for sealing the any punctures !

Air shot inflation (as mentioned up thread) or a compressor are the quickest ways to seal a tubeless tyre reliably - but I wouldn't expect such things to be available at an LEL or PBP control. Self sufficiency and being prepared dictate that a tube should always be carried in case of unsealable punctures in tubeless tyres.

There were more than a few riders who just weren't prepared.